We have a non-verbal too! Mom taught her sign language but that doesn't work for everybody

One of our alters is also completely non-verbal! He is an adult but what helps us sometimes is using pre-made “cards” with basic answers like ‘Yes’ ‘No’ ‘I can’t speak’ ‘it’s too hot’ ‘it’s too cold’ ‘I need food/water’ and anything else you might find useful! I think you can even find some pre-made ones online and use pictures if possible!

we use discord a lot, and in the case we go nonverbal we use nonverval emotes and emoji's to communicate! there's entire boards of nonverbal emotes on pinterest and google, and we also use a random drawing app to simply pre-write simple phrases we may need to use when nonverbal